Consumers looking for better deals on AT&T phones have until March 8th to grab them because after that date, AT&T phones will no longer be sold by most third-party online retailers.

Wirefly, which runs its own online storefront in addition to selling phones through Dell and Amazon.com, is a major dealer of AT&T phones and routinely undercuts pricing offered by AT&T’s own website and retail outlets.

Andy Zeinfeld, Wirefly’s CEO announced the change on the company’s website:

Unfortunately, circumstances prevent us from being able to deliver on this promise with regard to AT&T phones. It is therefore with regret that I must inform you that effective March, 2011, we will no longer offer AT&T products and services on Wirefly.com.

[…] As circumstances allow, we will work with AT&T toward the goal of offering their products and services again in the future.

LetsTalk made a similar announcement to their affiliates: “We’re reaching out to let you know of an upcoming change to our carrier offering.  Effective March 8th, LetsTalk as well as other web indirect agents […] will no longer be able to offer AT&T Wireless as a carrier option to our customers.”

The change likely indicates AT&T has radically reduced compensation for third party sellers.  Most earn discounts and commissions on phone sales — part of that savings is passed on to consumers in the form of lower prices, part is pocketed as revenue.

Consumers looking for bargains will pay the price.

Take the HTC Surround. AT&T sells the phone to new customers for $49.99. Wirefly sells the same phone for as low as $24.99, and LetsTalk gives you the phone for free with a new, 2-year contract.  Motorola’s Droid X that Verizon sells for $199 can be had for free from Wirefly or LetsTalk — no sales tax either.

Both AT&T and Verizon have been scaling back discounts and promotions on new phones in an effort to cut costs.